荧光假单胞菌ZX对葡萄采后灰霉病的防治

研究荧光假单胞菌（Pseudomonas fluorescens）ZX对葡萄采后灰霉病的防治效果。以“巨峰”葡萄为试材，测定P. fluorescens ZX的控病效果和生长动态，在离体条件下通过孢子萌发观察、挥发性物质抑菌测试、扫描电镜探究其对灰葡萄孢霉（Botrytis cinerea）的防治。结果表明，使用P. fluorescens ZX处理，葡萄果实的发病率仅为24.8%，明显低于对照组（发病率64.67%），病斑直径最小，可以明显抑制B. cinerea孢子萌发、芽管伸长。P. fluorescens ZX产生的挥发性物质具有较强的抑菌效果，并且能对B. cinerea有重寄生作用，破坏菌丝的正常形态。另外，无论是浸泡还是接种处理，P. fluorescens ZX都能在葡萄果实上快速地定殖生长。由此表明，P. fluorescens ZX通过抑制B. cinerea生长来控制葡萄采后灰霉病，为果实采后防腐保鲜提供一种新的选择。     

肉桂醛对番茄采后灰霉病的抑制作用及其对品质的影响

为研究肉桂醛对番茄采后灰霉病的抑制作用及其对番茄果实品质的影响,在离体条件下分别研究肉桂醛对
灰葡萄孢菌菌丝生长、孢子萌发的抑制作用,采用人工活体接种法研究肉桂醛对番茄果实灰霉病斑的控制作用,及
其对番茄自然发病果实的品质的影响。结果表明,肉桂醛对灰葡萄孢菌的菌丝生长和孢子萌发均有较好的抑制作
用,对菌丝生长的EC50值为95.6 μg/mL,质量浓度为60 μg/mL时对孢子萌发抑制率为100%;活体条件下肉桂醛能够
有效地抑制番茄果实采后灰霉病病斑的扩展,以4 000 μg/mL效果最好,且在此质量浓度条件下,对于降低果实质
量损失率,维持番茄硬度、可溶性固形物、可滴定酸和VC含量均具有较好的效果。4 000 μg/mL肉桂醛处理能够有
效地控制番茄采后灰霉病的发生及延长其保鲜期。     

山梨酸盐与钙胁迫对甜樱桃灰霉病抗性的诱导作用

以‘秦樱1号’樱桃为试材,研究不同质量浓度山梨酸钾（1、3、5、7 g/L）、CaCl2（5、10、15、 20 g/L）处理对离体灰霉菌的抑制效果,通过菌丝生长抑制率、扫描电子显微镜观察芽管生长及孢子萌发抑制率 筛选出最佳处理质量浓度。结果表明：与对照组相比,山梨酸钾、CaCl2处理均能不同程度地抑制灰霉菌菌丝的生 长,抑制灰霉菌芽管的伸长,降低孢子的萌发率,抑制效果随质量浓度的升高逐渐加强,20 g/L CaCl2、5 g/L山梨 酸钾处理抑制效果最好。以无菌水为对照,用采前喷20 g/L CaCl2、采后5 g/L山梨酸钾处理及二者复合处理接种灰 霉菌的甜樱桃,在（23±1）℃下存放5 d,通过测定发病率、病斑直径及相关酶活力探究不同处理对甜樱桃灰霉病 的抑制效果。在活体接种实验中,与对照组相比,20 g/L CaCl2、5 g/L山梨酸钾单独及复合处理均能有效抑制接种 到甜樱桃果实上灰霉菌的生长,减缓病斑的扩展,CaCl2与山梨酸钾处理能显著抑制樱桃果实中MDA含量上升,诱 导果实合成与积累抗性相关酶（多酚氧化酶、过氧化物酶、几丁质酶、β-1,3-葡聚糖酶）在接种1 d后或接种3 d后的 活力提高,以5 g/L山梨酸钾与20 g/L CaCl2复合处理抑制效果最好,该研究为降低由灰霉菌侵染引起的病害及采后 甜樱桃果实防腐保鲜提供了参考。     

Control of postharvest pear diseases using Rhodotorula glutinis and its effects on postharvest quality parameters

Rhodotorula glutinis was evaluated for its activity in reducing postharvest gray mold decay and blue mold decay of pear caused by Botrytis cinerea and Penicillium expansum respectively, and in reducing natural decay development of pear fruits, as well as its effects on postharvest quality of fruits. There was a significant negative correlation between concentrations of the yeast cells and infectivity of the pathogens. At concentrations of R. glutinis at 5x108 CFU/ml, the gray mold decay was completely inhibited after 7 days incubation at 20 degrees C, while the control fruit had 100% disease incidence and 2.15 cm lesion diameter respectively, at challenged with B. cinerea spores suspension of 1x105 spores/ml; No completely control was got to blue mold, when pear fruits stored at 20 degrees C for 7 d (challenged with P. expansum spores suspension of 5x104 spores/ml), but the decay was distinctly prevented with 20% and 0.60 cm of disease incidence and lesion diameter respectively, while the control fruits were 100% and 2.74 cm, respectively. Rapid colonization of the yeast in wounds was observed during the first 1 d at 20 degrees C, and then the populations stabilized for the remaining storage period. On pear wounds kept at 4 degrees C, rapid colonization of the yeast in wounds was observed during the first 3 d, and then the increase in population density of R. glutinis turned slow, which continued over 6 d after application of the antagonist until it reached a high level. Then, the populations stabilized for the remaining storage period. In the test on PDA plates, R. glutinis significantly inhibit the growth of B. cinerea and P. expansum. Spore germination of pathogens in PDB was greatly controlled in the present of living yeast cell suspensions. R. glutinis significantly reduced the natural development of decay of pear following storage at 20 degrees C for 7 days or at 4 degrees C for 30 days followed by 20 degrees C for 5 days, and did not impair quality parameters, including mass loss, firmness, TSS, ascorbic acid or titratable acidity. Thus, the application of R. glutinis can be an alternative to chemicals for control of postharvest diseases on pear fruits.     

2,4-表油菜素内酯对葡萄果实采后灰霉病的抑制作用机理

为研究2,4-表油菜素内酯（2,4-epibrassionolide,EBR）处理对‘巨峰’葡萄果实采后灰霉病的抑制效果及作用机制,将葡萄果实经5 μmol/L EBR溶液处理12 h后刺伤接种灰葡萄孢（Botrytis cinerea）病原菌,然后置于25 ℃下贮藏60 h。结果显示：EBR处理有效抑制了葡萄采后灰霉病的发生和病斑直径的扩展,与单一接种病原菌和EBR处理相比,先用EBR处理后接种B. cinerea葡萄果实展现出更强、更快的抗病反应,表现为几丁质酶、β-1,3-葡聚糖酶和苯丙氨酸解氨酶等抗病相关酶活力及总酚含量显著提高（P＜0.05）,H2O2积累及超氧化物歧化酶、过氧化氢酶、抗坏血酸过氧化物酶活力提高,同时VvCHI、VvGNS和VvPAL-like抗病基因表达显著增加（P＜0.05）;体外实验发现,EBR处理可显著抑制B. cinerea孢子的萌发,但对芽管伸长长度没有显著影响。结论：EBR处理主要是通过敏化反应机制诱导提高葡萄果实的抗病性,从而减轻灰霉病的发生。     

纳他霉素对葡萄采后交链孢菌的抑制作用

交链孢菌(Alternaria sp.)是导致鲜食葡萄采后腐烂变质的主要病原菌。以葡萄采后交链孢菌为病原菌,采用生长速率法、悬滴法及活体接种法,研究了不同浓度纳他霉素抑菌液对菌丝生长、孢子萌发的抑制作用以及对果实的防病效果。结果表明,适宜浓度的纳他霉素对葡萄采后交链孢菌的抑制效果明显,对菌丝生长及孢子萌发的抑菌中浓度(EC50)分别为83.48和89.47mg/L;当抑菌液浓度达200mg/L时,对菌丝生长和孢子萌发的抑制率均达到80%以上。活体接种实验结果表明,浓度为200mg/L的纳他霉素抑菌液可显著(p<0.05)抑制葡萄采后交链孢菌引起的霉烂变质。综上,纳他霉素处理对葡萄采后交链孢菌具有较好的抑制活性,可作为葡萄采后绿色保鲜剂的潜在资源。      

Effect of yeast antagonist in combination with heat treatment on postharvest blue mold decay and Rhizopus decay of peaches

The potential of using heat treatment alone or in combination with an antagonistic yeast for the control of blue mold decay and Rhizopus decay of peaches caused by Penicillium expansum and Rhizopus stolonifer respectively, and in reducing natural decay development of peach fruits, as well as its effects on postharvest quality of fruit was investigated. In vitro tests, spore germination of pathogens in PDB was greatly controlled by the heat treatment of 37 degrees C for 2 d. In vivo test to control blue mold decay of peaches, heat treatment and antagonist yeast, as stand-alone treatments, were capable of reducing the percentage of infected wounds from 92.5% to 52.5% and 62.5%, respectively, when peach fruits stored at 25 degrees C for 6 d. However, in fruit treated with combination of heat treatment and Cryptococcus laurentii, the percentage of infected wounds of blue mold decay was only 22.5%. The test of using heat treatment alone or in combination with C. laurentii to control Rhizopus decay of peaches gave a similar result. The application of heat treatment and C. laurentii resulted in low average natural decay incidences on peaches after storage at 4 degrees C for 30 days and 20 degrees C for 7 days ranging from 40% to 30%, compared with 20% in the control fruit. The combination of heat treatment and C. laurentii was the most effective treatment, and the percentage of decayed fruits was 20%. Heat treatment in combination with C. laurentii had no significant effect on firmness, TSS, ascorbic acid or titratable acidity compared to control fruit. Thus, the combination of heat treatment and C. laurentii could be an alternative to chemicals for the control of postharvest decay on peach fruits.     

采后纳米氧化锌对苹果黑斑病和青霉病的控制

通过离体(in vitro)和体内(in vivo)实验,研究了纳米氧化锌处理对苹果采后主要致腐病菌Alternaria alternata和Penicillium expansum生长的抑制及对病害的控制效果。结果表明:纳米氧化锌对两种病菌的菌丝生长均具有明显的抑制作用,且抑制效果随浓度的升高而增加,其中20%的纳米氧化锌对A.alternata和P.expansum的抑菌率分别达到86.85%和49.60%,对前者抑制效果显著优于后者。20%纳米氧化锌处理对A.alternata孢子萌发的抑制较对照下降了87.37%,而15%纳米氧化锌处理对P.expansum孢子萌发的抑制较对照下降了94.56%。同时纳米氧化锌也显著降低了损伤接种A.alternata和P.expansum苹果病斑直径的扩展,其中以5%纳米氧化锌处理效果最好,分别与对照相比降低了76.24%和65.32%,更高浓度处理并没有增强抑制效果。由此表明,纳米氧化锌可通过直接抑菌作用来减轻苹果黑斑病和青霉病的发生。      

Fungitoxic activity of 12 essential oils against four postharvest citrus pathogens: chemical analysis of thymus capitatus oil and its effect in subatmospheric pressure conditions.

The fungitoxic activity against Penicillium digitatum, Penicillium italicum, Botrytis cinerea, and Alternaria citri of 12 essential oils (EOs) distilled from medicinal plants is reported. The results of the in vitro trials show strong fungitoxic activity of Thymus capitatus (L.) Hofmgg EOs, which inhibited the growth of the four fungi at a concentration of 250 ppm (vol/vol). The other 11 essences reduced the development of the fungi from 95 to 9% at 250 ppm (vol/vol). The fungitoxic activity of T. capitatus EOs (75, 150, and 250 ppm) on healthy orange fruits, inoculated with P. digitatum (10(8) conidia ml(-1)) by spraying and placed in 10-liter desiccators, was weak at atmospheric pressure (3 to 10% inhibition at all three concentrations), while in vacuum conditions (0.5 bar), conidial mortality on the exocarp was high (90 to 97% at all three concentrations). These data proved not to be statistically different from treatments with thiabendazole-TBZ (2,000 ppm). Scanning electron microscope observations showed that T. capitatus EO vapors altered the morphology of P. digitatum hyphae and conidia. The gas-chromatographic analyses of thyme EO indicated that carvacrol was present at 81 to 83%, p-cymene at 4.5 to 5%, gamma-terpinene at 2.6 to 3.3%, caryophyllene at 1.5 to 1.6%, beta-myrcene at 1.6%, and linalool at 1.1 to 1.2%. Carvacrol proved to be the most important fungitoxic compound among the thyme EO constituents, but, unlike thyme EO, it caused alterations to the fruit at the concentration of 75 ppm.     

纳米TiO_2-壳聚糖复合涂膜对砂糖橘的保鲜效果

以砂糖橘为试验材料,从腐烂果实上分离并鉴定腐败菌,筛选合适的壳聚糖-纳米TiO2复合涂膜,研究该涂膜对砂糖橘采后贮期品质的影响及其体外抑菌效果。结果表明:引起砂糖橘致病的主要真菌为指状青霉(Penicillium digitatum);当涂膜液中壳聚糖、纳米TiO2的质量分数皆为2%时,涂膜组保持较高的果实硬度、可溶性固形物、可滴定酸和VC含量;该复合涂膜还能有效的抑制P.digitatum的生长及其病斑的扩展。     

拮抗酵母菌挥发物单体对草莓灰霉病的防治效果

为研究葡萄汁有孢汉逊酵母（Hanseniaspora uvarum）挥发物单体对草莓灰霉病的防治作用,研究了21 种挥发物单体离体条件下对灰葡萄孢的抑制作用,以及活体条件下3-羟基己酸乙酯、癸酸乙酯、桂皮醛和辛酸乙酯对草莓果实灰霉病的防治作用。结果表明：除月桂酸外,其余20 种单体均对灰葡萄孢菌丝生长和孢子萌发有抑制作用,其中桂皮醛剂量为62.5 μL/L时完全抑制菌丝生长,625 μL/L时可以完全抑制孢子萌发;活体条件下,4 种单体均能有效地抑制草莓果实采后灰霉病的发生,保持草莓色泽,延缓草莓可溶性固形物质量分数、可滴定酸质量分数、硬度等质构特性的下降,其中桂皮醛防治草莓灰霉病效果最好,具有商业开发前景。     

香菇多糖对烟草灰霉病的防治效果研究

为挖掘香菇多糖( Lentinus,LTN)对常见植物病原菌的防治效果,采用生长速率法和菌丝块接种法检测了香菇多糖对常见植物病原真菌菌丝生长、孢子萌发、种子萌发和烟苗生长的影响及对烟草灰霉病( Tobacco grey mould)的温室防治效果.结果表明:香菇多糖对7种常见植物病原真菌均具有较好的抑制作用,其中1％香菇多糖对烟草灰霉病原菌的抑制活性最高,抑菌圈直径达39.45 mm.香菇多糖能致使烟草灰霉病原菌菌丝分支增多,膨大畸形等异常生长现象,孢子萌发抑制率高达97.63％,孢子致畸率为53.68％.且香菇多糖对烟草种子萌发有较明显的促生作用.盆栽试验表明1％香菇多糖溶液对烟草灰霉病的防治效果达85.05％.     

盐酸小檗碱抑制指状青霉的作用机制

本实验主要对盐酸小檗碱(berberine hydrochloride,BH)抑制指状青霉(Penicillium digitatum)生长的活性以及可能的作用机制进行探讨.结果表明,BH抑制指状青霉生长的最低抑菌质量浓度(minimum inhibitory concentration,MIC)和最低杀菌质量浓度(m...     

烟草灰霉病菌嘧菌酯抗药性突变菌株的诱导及其生物学习性分析

  目的  为了解烟草灰霉病菌对嘧菌酯潜在的抗药性风险。  方法  通过紫外诱变诱导烟草灰霉病菌对嘧菌酯的抗药性突变菌株,分析其对嘧菌酯的敏感性和生物学习性。  结果  嘧菌酯对烟草灰霉病菌分生孢子萌发具有较高的抑制作用,其抑制孢子萌发的EC₅₀为2.28 mg/L。紫外诱变获得5株不同抗性水平的嘧菌酯抗药性突变菌株,对嘧菌酯抗性是诱变前菌株的1.69~10.41倍。继代培养11代后,各突变菌株对嘧菌酯的敏感性稳定;突变菌株菌丝生长速度高于或低于初始菌株;所有突变菌株的分生孢子产量和萌发率均低于初始菌株;突变菌株菌核产量同初始菌株一致或有所降低;所有突变菌株具有致病力,部分致病力强于初始菌株。  结论  嘧菌酯对烟草灰霉病菌分生孢子萌发具有较强的抑制作用;若使用嘧菌酯防治烟草灰霉病,存在烟草灰霉病菌对嘧菌酯产生抗药性的风险。      

指状青霉V-ATP酶H亚基蛋白的功能

目的:通过基因干扰和过表达技术,研究V-ATP酶H亚基(V-ATPase membrane subunit H,VMAH)蛋白在柑橘绿霉病菌指状青霉生长中的生理功能,及其作为抗柑橘绿霉病药物作用靶点的可行性.方法:采用菌丝生长法和孢子萌发法,研究沉默和过表达VMAH基因对正常和胁迫条件下指状青霉细胞生长特性的影响.结果...     

抗菌肽Jelleine-I对采后柑橘果实绿霉病的控制作用

研究抗菌肽Jelleine-I对指状青霉（Penicillium digitatum）生长的影响及可能的作用机理,并采用损伤接种的方法评价Jelleine-I对柑橘果实采后绿霉病的控制效果。结果表明,Jelleine-I能明显抑制P. digitatum的生长,其最小抑菌浓度和最小杀菌浓度分别为6.25 mmol/L和12.5 mmol/L;同时,其能有效控制柑橘果实采后绿霉病的发生。经Jelleine-I处理后的P. digitatum菌丝体细胞膜通透性增加,细胞间隔膜损坏,细胞内绿色SYTOX Green荧光强度增加,细胞间蓝色Calcofluor White荧光减少。此外,经Jelleine-I处理后的P. digitatum菌丝体胞外电导率以及胞内核酸物质泄漏量均显著增加（P＜0.05）。综上,Jelleine-I通过破坏P. digitatum细胞膜结构完整性,引起胞内物质泄漏,加速P. digitatum死亡,从而有效控制柑橘果实采后绿霉病的发生。     

臭氧对葡萄灰霉病的抑制效果

研究不同臭氧处理方式对离体及接种在活体葡萄上的灰霉菌的抑制作用,为降低采后葡萄贮藏过程中灰霉病带来的损失提供理论依据。在(20±1)℃条件下用不同剂量的臭氧(0、30、60、90μL/L)对离体灰霉菌分别处理不同时间(5、10、15 min),通过测定菌丝生长长度、孢子形成抑制率、孢子细胞膜完整性及扫描电镜观察来探究臭氧对其抑制效果。用上述4种剂量的臭氧分别对接种了灰霉菌的‘红地球’葡萄处理15 min后(20±1)℃条件下存放5 d。通过测定发病率、病斑直径及相关酶活性来观察臭氧对葡萄灰霉病的控制效果。结果表明:在离体实验中,与对照相比,不同剂量的臭氧对离体灰霉菌处理不同时间后,灰霉菌菌丝的生长均受到了不同程度抑制,随贮藏时间延长抑制效果逐渐减弱;灰霉菌的产孢子率显著下降,部分孢子的细胞膜完整性被破坏,臭氧剂量越高、处理时间越长,效果越好。在接种了灰霉菌的活体实验中,与对照组相比,用60μL/L和90μL/L剂量臭氧处理接种灰霉菌的葡萄果实后,灰霉菌在果实上的生长明显受到抑制;臭氧处理可以使果实丙二醛含量积累减慢,维持较高的抗氧化酶活性。综合分析,臭氧通过抑制灰霉菌菌丝在葡萄果实上的生长和诱导葡萄果实提高抗性来抵抗灰霉菌的侵染,采用90μL/L剂量臭氧处理15 min对离体条件下和接种在‘红地球’葡萄活体上的灰霉菌抑制效果均为最好。     

5株桃、李果实采后褐腐病菌鉴定、rDNA ITS序列与碳源代谢指纹图谱分析

从采后贮藏过程中发病的桃、李果实中分离到5株丝状病原真菌。对其进行形态学特征观察以及核糖体rDNA ITS序列分析和95种碳源代谢指纹图谱分析。结果表明:5株病原真菌均为果生链核盘菌(Monilinia fructicola),其中091#和089#菌与Monilinia fructicola(FJ515894)的亲缘关系较近。5株褐腐病菌对D-果糖、麦芽糖、蔗糖等共56种碳源的代谢能力相同,包括51种最适碳源和5种不可利用碳源,其中Monilinia fructicola 091#与089#的代谢指纹图谱最接近,而Monilinia fructicola 086#、071#、072#的代谢指纹图谱最接近。因此利用rDNA ITS序列和碳源代谢指纹图谱均可区分桃、李果实5株褐腐病菌不同菌株之间的差异,且两种方法具有可比性。     

The effects of composite coatings containing chitosan and Mentha (piperita L. or x villosa Huds) essential oil on postharvest mold occurrence and quality of table grape cv. Isabella

The effects of coatings containing shrimp chitosan and the essential oil from Mentha piperita L. (MPEO) or M. villosa Huds (MVEO) to control common mold infections in table grape cv. Isabella (Vitis labrusca L.) that were caused by Aspergillus niger, Botrytis cinerea, Penicillium expansum and Rhizopus stolonifer were evaluated. The effects of the coatings on physicochemical and sensory characteristics of the grapes were also assessed. The coatings containing chitosan (4, 8 mg/mL) and MPEO or MVEO (1.25, 2.5, 5 μL/mL) delayed the mold growth and reduced the incidence of infections caused by all test fungi in grapes during storage at room and low temperatures. The coatings (chitosan 4 mg/mL; MPEO or MVEO 1.25, 2.5 μL/mL) did not negatively affect the physicochemical and sensory characteristics of grapes. From these results, coatings containing chitosan and MPEO or MVEO are potential postharvest treatments to control common mold infections in table grape cv. Isabella.Industrial relevanceIn table grapes, the reduction of losses resulting from fungal rot is a major goal of postharvest technology, which seeks to use effective methods to control the contamination and the growth of phytopathogenic fungi. However, the negative consumer perception of synthetic fungicides used for many years to solve the problem of mold infections in table grapes and the development of fungicide-resistant strains have impelled researchers to study the efficacy of natural compounds against postharvest pathogenic fungi. In this context, edible coatings composed of chitosan and essential oils have been considered as an environmentally friendly and added-value technology to control fungal postharvest decay in table grapes because of their biodegradability and lack of phytotoxicity. In this study, the authors evaluated composite coatings that contained shrimp chitosan and reduced amounts of Mentha (piperita L. or x vilosa Huds) essential oil as postharvest treatment to control the occurrence of mold infections caused by fungi in table grape cv. Isabella (Vitis labrusca L.), and their effects on the quality attributes of this fruit during storage. The tested composite coatings are presented as possible alternative technologies to control fungal infections and related post-harvest losses in table grape cv. Isabella.     

苹果采后灰霉病抗性生理差异分析

以‘秦冠’、‘富士’苹果果实为材料,对损伤接种灰葡萄孢(Botrytis cinerea Pers.)后果肉组织抗病相关物质及酶活力变化进行分析测定,揭示苹果采后灰霉病抗性差异的生理机制。结果表明:接种B.cinerea后,两种果实的发病率和病斑直径存在差异,其中‘秦冠’苹果发病率和病斑直径显著小于‘富士’苹果(P0.05);进一步研究发现抗病品种果肉组织中苯丙氨酸解氨酶、过氧化物酶、多酚氧化酶、几丁质酶、β-1,3-葡聚糖酶活力均高于感病品种,从而促进抗病品种果肉中类黄酮和木质素的积累,降低膜脂过氧化程度,减少丙二醛的产生,提高了果实的抗病性,但总酚含量‘秦冠’苹果低于‘富士’苹果。研究结果可以为苹果灰霉病抗性鉴定和筛选抗灰霉病苹果资源提供理论指导。